The present invention relates to a method and apparatus for controlling data communication in a copying system.
Recent copying machines must speedily and exactly handle a large number of and various types of documents. To meet such requirements, the copying machine is systematized. For example, it is used in combination of peripheral machines, such as an automatic document feeder (ADF) and sorters.
In such a systematized copying machine (referred to as a copying system), the copying machine contains a host CPU, and the peripheral machines also contain slave CPUs. The slave CPUs are under control of the host CPU via an interface. For the data communication among those CPUs, the copying machine is provided with a plurality of serial ports to respectively be coupled with the ADF and sorters. Also each of the sorters has a plurality of serial ports to be coupled with the copying machine and the other sorters. Use of the plurality of serial ports is uneconomical and will increase the cost to manufacture.